Pro SL (2020–2024) vs. Aethos (2026)

A

Rose · Road · 700c · tyres up to 28 mmManufacturer data · as of Oct 25, 2026Source

Cockpit: 20 mm spacers · 100 mm stem · -6°

SpacersStemAngle °

Saddle: same saddle height · 0 mm setback · centred (default)

Saddle heightSetbackForward (+)/back

B

Specialized · Road · 700cManufacturer data · as of Oct 25, 2026Source

Cockpit: 20 mm spacers · 100 mm stem · -6° (stock)

SpacersStemAngle °

Saddle: same saddle height · 0 mm setback · centred (default)

Saddle heightSetbackForward (+)/back

Reach: Horizontal distance from the bottom bracket to the top of the head tube. More reach = more stretched-out position. · grid 10 cm

Aethos (2026) 54 vs. Pro SL (2020–2024) 55: 6 mm less stack · 0.5° steeper head angle

Measure	Pro SL (2020–2024) 55	Aethos (2026) 54
Frame
Stackmm	565	559−6
Reachmm	383	384+1
Stack / Reach	1.47	1.46−0.02
Head angle°	72.0°	72.5°+0.5°
Seat angle°	74.0°	74.0°±0
Head tubemm	163	150−13
Seat tubemm	505	490−15
Top tube (effective)mm	545	544−1
Chainstaymm	409	410+1
Rear centre (horizontal)mm	402	403+1
Wheelbasemm	994	992−2
Front centremm	596	594−2
BB dropmm	73	75+2
BB heightmm	266	267+1
Fork offsetmm	46	50+4
Trailmm	62	55−7
Fork axle-to-crownmm	–	372
Cockpit & riding position
Bar reachmm	468	470+2
Bar stackmm	623	617−6
Saddle – barmm	667	668+2
Saddle-to-bar dropmm	69	75+6
Tyre clearancemm	28	–

italic = calculated · tap a row to pin the measure in the drawing · Δ relative to Pro SL (2020–2024)

Size finder · transfer your fit

Transfer your riding position to a new bike

Enter your well-fitting bike with saddle height, seatpost and cockpit. For every size of the new bike we calculate the stem, spacers, saddle height, setback and saddle position that reproduce the same contact points. This is a geometric approximation without guarantee and does not replace a professional bike fit.

1

Your bike – how you sit today

Saddle

mmmmmm

Cockpit

mmmm°

Saddle: 198 mm behind · 692 mm above BB
Handlebar: 468 mm ahead · 623 mm above BB
Saddle–bar: 667 mm · drop 69 mm

Saddle height: bottom bracket centre to top of saddle along the seat-tube axis. Saddle fore/aft: + forward, − back. Spacers incl. top cap, handlebar centre = stem clamp.

2

New bike – what do I need to set up?

Choose the bike you want to transfer your position to. We calculate every size.

Explore

All frame sizes at a glance

All frame sizes by stack and reach or any other measure – click a dot or line to add the bike to the comparison.

1040 of 1040 sizes · 159 models

Each dot is a frame size. Coloured dots with a letter = current comparison.

Similar to Pro SL (2020–2024) 55

only Road

Similarity over the axes of the geometry profile below; stack and reach count 1.5×. The best-matching size per model, filters are respected.

Geometry profile

Each line is a frame size across all selected measures. Drag on an axis to filter a range – this also affects the chart and the similarity list.

Drag on an axis to filter a range · click a line to compare the bike

Add a bike

BrandModelModel year *CategoryWheel (front)Wheel rearTyre clearance, max. (mm)Source (manufacturer page with geometry table) *

Paste a geometry table

Select the table on the manufacturer's page, copy it and paste it here. Sizes as columns or rows, German or English; values like “435/432” for flip chips are recognised.

Sizes (mm / degrees · * required · setting e.g. “High”, “Low”, “Mullet”)

Size*	Setting	Stack*	Reach*	Head ∠ °*	Seat ∠ °*	Head tube*	Chainstay*	BB drop*	BB drop rear	Seat tube	Top tube	Wheelbase	Fork offset	Axle-to-crown	BB height	Front ctr.	Trail	Stem	Spacers